Previous research indicates that mildly depressed college students accurately perceive environmental contingencies. These findings, however, run contrary to predictions from clinically-based, cognitive models of depression. Researchers have suggested that, unlike nondepressives, mild depressives lack the motive to enhance self-esteem and thus do not distort their perception of contingencies. The present research tests the esteem enchancement hypothesis and determines whether past research with mildly depressed college students generalizes to clinical depressives. This study investigates the cognitive processing of five inpatient groups; clinical depressives, mildly depressed schizophrenics, mildly depressed general surgery patients, nondepressed schizophrenics, and nondepressed general surgery patients. Subjects will be given six tasks, each consisting of 20 trials of pressing or not pressing a computer key to make a light on the screen flash on. After each task subjects estimate their degree of control over light onset. Actual control over outcomes will be manipulated to allow the detection of both over- and underestimations of control. This study predicts that nondepressives will overestimate control; mild depressives will show accurate judgement of control; and clinical depressives will underestimate control. This study also tests whether deviations from accurate perception are maintained when they are clearly maladaptive, i.e., when a contingency is placed on accuracy. This is the first study to directly assess depressed psychiatric patients; judgment of control, and it introduces significant methodological improvements over previous research. results will clarify current discrepancies between cognitive theories and empirical findings, advance our understanding of depression, and prepare the way for improvements in treatment intervention.